:root{color-scheme:dark;font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,sans-serif;line-height:1.5;--sq-size: clamp(36px, min(9vmin, 10vw), 72px)}*{box-sizing:border-box;margin:0;padding:0}html,body,#root{min-height:100vh;background:#1a1a2e;color:#e0e0e0}.app{min-height:100vh;min-height:100dvh;display:flex;justify-content:center;align-items:center;padding:1rem}.game-layout{display:flex;gap:2rem;align-items:flex-start;max-width:900px}.board-area{display:flex;flex-direction:column;gap:.5rem}.chess-board-container{position:relative;display:flex;gap:0}.rank-labels{display:flex;flex-direction:column;justify-content:space-around;padding-right:.4rem}.rank-label{height:var(--sq-size);display:flex;align-items:center;font-size:.75rem;color:#fff6;font-weight:500}.file-labels{display:flex;justify-content:space-around;padding-top:.3rem;margin-left:1.2rem}.file-label{width:var(--sq-size);text-align:center;font-size:.75rem;color:#fff6;font-weight:500}.chess-board{display:flex;flex-direction:column;border:2px solid #444;border-radius:4px;overflow:hidden;box-shadow:0 8px 32px #00000080}.board-row{display:flex}.sq{width:var(--sq-size);height:var(--sq-size);display:flex;align-items:center;justify-content:center;cursor:pointer;position:relative;transition:background .1s;touch-action:manipulation;-webkit-tap-highlight-color:transparent}.sq-light{background:#f0d9b5}.sq-dark{background:#b58863}.sq-selected{background:#f7ec5a!important}.sq-last-move{background:#aaf0aa!important}.sq-check{background:radial-gradient(ellipse at center,#ff4444 0%,#cc0000 40%,transparent 70%);animation:check-pulse 1.5s ease-in-out infinite}@keyframes check-pulse{0%,to{box-shadow:inset 0 0 12px #f009}50%{box-shadow:inset 0 0 20px #ff0000e6}}.piece{font-size:calc(var(--sq-size) * .7);-webkit-user-select:none;user-select:none;line-height:1;filter:drop-shadow(1px 1px 2px rgba(0,0,0,.5));z-index:1}.piece-white{color:#fff;text-shadow:0 0 3px rgba(0,0,0,.7)}.piece-black{color:#222;text-shadow:0 0 3px rgba(0,0,0,.3)}.move-dot{width:calc(var(--sq-size) * .25);height:calc(var(--sq-size) * .25);background:#00000040;border-radius:50%;position:absolute;pointer-events:none}.capture-ring{width:calc(var(--sq-size) * .85);height:calc(var(--sq-size) * .85);border:calc(var(--sq-size) * .08) solid rgba(0,0,0,.25);border-radius:50%;position:absolute;pointer-events:none;box-sizing:border-box}.side-panel{background:#16213e;border:1px solid #333;border-radius:8px;padding:1.5rem;min-width:240px;max-height:calc(var(--sq-size) * 8 + 4rem);display:flex;flex-direction:column}.game-title{font-size:1.25rem;font-weight:700;margin-bottom:.75rem;color:#e0e0e0}.status-bar{display:flex;align-items:center;gap:.5rem;padding:.6rem .8rem;background:#ffffff0d;border-radius:6px;margin-bottom:1rem}.status-dot{width:10px;height:10px;border-radius:50%;flex-shrink:0}.status-dot.white{background:#fff;border:1px solid #888}.status-dot.black{background:#333;border:1px solid #666}.status-text{font-size:.9rem;font-weight:500}.move-history{flex:1;overflow-y:auto;margin-bottom:1rem;padding:.5rem;background:#0003;border-radius:4px;min-height:120px;max-height:360px}.no-moves{color:#ffffff4d;font-style:italic;font-size:.85rem;text-align:center;padding:1rem 0}.move-pair{display:flex;gap:.5rem;padding:.2rem 0;font-size:.85rem}.move-number{color:#fff6;min-width:1.8rem;font-family:ui-monospace,monospace}.move-notation{font-family:ui-monospace,monospace;min-width:3.5rem}.controls{display:flex;gap:.5rem;flex-wrap:wrap}.btn{flex:1;padding:.5rem .75rem;border:1px solid #555;border-radius:4px;background:#2a2a4a;color:#e0e0e0;cursor:pointer;font-size:.8rem;font-weight:500;transition:background .15s,border-color .15s;touch-action:manipulation;-webkit-tap-highlight-color:transparent}.btn:hover:not(:disabled){background:#3a3a5a;border-color:#777}.btn:disabled{opacity:.4;cursor:not-allowed}.btn-primary{background:#4a6fa5;border-color:#5a8fc5}.btn-primary:hover:not(:disabled){background:#5a8fc5}.captured-row{display:flex;align-items:center;flex-wrap:wrap;gap:.15rem;min-height:1.6rem;padding:0 .3rem}.captured-piece{font-size:1.1rem;opacity:.8}.material-advantage{font-size:.75rem;font-weight:600;color:#fff9;margin-left:.3rem}.promotion-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#0009;display:flex;align-items:center;justify-content:center;z-index:100}.promotion-dialog{background:#1e2a4a;border:1px solid #555;border-radius:12px;padding:1.5rem;text-align:center}.promotion-dialog p{margin-bottom:1rem;font-weight:600}.promotion-choices{display:flex;gap:.75rem}.promotion-btn{width:64px;height:64px;border:2px solid #555;border-radius:8px;background:#2a3a5a;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:background .15s,border-color .15s}.promotion-btn:hover{background:#3a4a6a;border-color:#888}.promotion-btn .piece{font-size:2.5rem}@media(max-width:700px){.game-layout{flex-direction:column;align-items:center;gap:1rem}.side-panel{min-width:unset;width:100%;max-width:calc(var(--sq-size) * 8 + 3rem);max-height:unset}}@media(max-width:480px){:root{--sq-size: clamp(32px, 11vw, 48px)}.app{padding:.5rem;align-items:flex-start}.game-layout{gap:.75rem;width:100%}.board-area{width:100%;align-items:center}.file-labels{margin-left:1rem}.rank-label{font-size:.6rem;padding-right:.2rem}.file-label{font-size:.6rem}.side-panel{padding:1rem;border-radius:8px}.game-title{font-size:1.1rem}.status-bar{padding:.5rem .6rem;margin-bottom:.75rem}.status-text{font-size:.8rem}.move-history{min-height:80px;max-height:200px;padding:.4rem}.move-pair{font-size:.8rem}.controls{gap:.4rem}.btn{padding:.6rem .5rem;font-size:.75rem;min-height:40px}.captured-row{min-height:1.2rem;padding:0 .5rem}.captured-piece{font-size:.9rem}.promotion-btn{width:56px;height:56px}.promotion-btn .piece{font-size:2rem}}@media(max-width:360px){:root{--sq-size: 32px}.controls{flex-direction:column}.btn{width:100%}}